1. Field of the Disclosure
This disclosure relates to a bottle cap adapter, a bottle supply system, and a system comprising a bottle cap adapter and a bottle supply system for supplying liquids. Both, the bottle cap adaptor as well as the bottle supply system apply particularly for viscous liquids, e.g. photoresist for photolithography.
2. Discussion of the Background Art
The high cost of photochemicals, e.g., photoresist, necessitates that all material should be used in the process to the last drop. Current systems rely on a dip tube to draw the liquid out of bottles of liquids, e.g. photochemicals, which always leads to a small percentage of the liquid in the bottom being wasted.
Moreover, current systems relying on a dip tube to draw the liquid out of the bottle have problems with the exchange of the bottle: air bubbles can be trapped at the bottom of the tube which may then be transported in the process lines. The air bubble, if not purged out, will cause process defects leading to losses as well as increased production costs. A common method for avoiding such defects is to purge the bubble after each exchange of the bottle through a bubble trap which results in a further waste of the chemical that could otherwise be used for the process.
Other systems exist that may draw nearly 99% of the fluid out of the container. However, these container only fit to costly packaging systems such as the so called “NOWPACK” offered by ATMI/NOW.
An inverted bottle system is offered by Phenix Semicron Corp. However, this system is rather bulky and may need more space in an existing tool than could be afforded in typical coater modules and/or developer modules. Furthermore, the inverted bottle system by Phenix Sem Corp. is particularly suitable for lower viscosity materials and may not function well with higher viscosity materials without modifications.
In addition, conventional systems indicate the level of the fluid remaining in the bottle by either using an empty detection system which also increases the potential for waste and bubble infusion into the process line or using a scale which provides a continuous indication of the level. However, a conventional scale system may be prone to several problems as the load being imposed by differing tubing from one setting to another.
It is a gist of the disclosure that instead of the photoresist being pumped from the bottle, the bottle is inverted, i.e. to turn the bottle upside down. With this arrangement, the photoresist is supplied by means of gravity rather than using a pump such that the generation of air bubbles during the pumping is excluded ab initio. Moreover, since the photochemical, e.g., the photoresist, at first is fed to a reservoir, there is no interruption of the supply during the bottle exchange, due to the buffer volume in the reservoir. Due to a vent tube, no additional venting of the bottle, in particular during the bottle exchange is needed.
It is an object of the disclosure to provide a bottle cap adapter for supplying liquids, a bottle supply system, and a system comprising a bottle cap adapter and a bottle supply system for supplying liquids.